The overarching goal of this Pathway to Independence Award is to facilitate the development of Csar G. Escobar-Viera, PhD, MD, MPH, into an independent researcher, with expertise in advanced quantitative and qualitative methods to determine the role of social media on depression among lesbian, gay, and bisexual U.S. young adults (LGBYA). Ultimately, the PI seeks to leverage evidence-based SM interventions to ameliorate depression among LGBYA, which will ultimately help to reduce mental health disparities for this group. This long-term goal will be achieved via a 5-year training and research plan that will launch Dr. Escobar-Viera?s independent program of research and academic career. The career objectives of this award are to: (1) become an expert in the field of social media research applied to depression; (2) advance the PI?s knowledge in LGBT mental health disparities; and (3) gain expertise in the application of advanced quantitative and qualitative methodologies. These career objectives will be achieved via formal coursework, trainings, seminars, national conferences, mentorship, and research experience. The knowledge derived from this training plan will prepare Dr. Escobar-Viera to pursue the following aims. In the first aim, pre-existing survey data from a nationally- representative sample of young adults will be leveraged to explore cross-sectional associations between SMU and depression among LGBYA. During the second aim, qualitative assessments about SMU and depression among LGBYA. The influence of SMU on depression will be explored by inquiring about what type of use is helpful and generates social support and which use result in negative feelings and experiences (e.g., discrimination). Finally, the third aim will consist of a longitudinal examination of the associations between SMU and depression among LGBYA. Results of this aim will inform the PI?s next step of developing an SM-based intervention for LGBYA at risk for depression, mitigating identified risk factors while enhancing protective ones. Feasibility and efficacy of the intervention will be then tested via a series of R21 and R01 projects during Dr. Escobar-Viera?s independent research career. An outstanding team of experts in LGBT research, qualitative research, longitudinal analyses, survey research, and mobile and social media interventions will provide mentorship to ensure the success of this project. Brian Primack, MD, PhD, will serve as the primary mentor. Dr. Primack leveraged his own K07 into multiple R01 and R21 awards. Co-mentorship will be provided by Michael Marshal, PhD and Ron Stall, PhD. Moreover, Galen Switzer, PhD and Sherry Pagoto, PhD will serve as consultants. This study proposes to lay a theoretical foundation needed to develop evidence-based social media interventions to improve mental health outcomes among sexual minorities. In addition, it will contribute to developing a model to study the influence of social media on health disparities among other minority groups. This award will forge the PI?s pathway to independence by laying a foundation for a career in social media interventions to reduce depression among LGBYA, thus decreasing health disparities for this population.